A process for the preparation of 1-substituted-5(4H)-tetrazolinones

Abstract: A process for the production of 1-substituted-5(4H)-tetrazolinones represented by the general formula: wherein R¹ represents optionally substituted C₁₋₁₂ alkyl, optionally substituted C₃₋₈ cycloalkyl, optionally substituted C₃₋₈ alkenyl, optionally substituted C₃₋₈ alkynyl, or a group represented by the general formula wherein Ar represents optionally substituted phenyl, optionally substituted naphthyl or an optionally substituted five- to seven-membered heterocyclic ring, R³ represents hydrogen or C₁₋₄ alkyl, and n is 0, 1, 2, 3 or 4, which comprises reacting the thioxo group of 1-substituted-5(4H)-tetrazolinethiones represented by the general formula (II) wherein R¹ has the same meaning as mentioned above, with ethylene oxides of the general formula (III) wherein R² represents hydrogen, methyl or ethyl, in the presence of a base, and in the presence of water or an alcohol or a solvent mixture thereof.

Description: The present invention relates to a process for the preparation of 1-substituted-5(4H)-tetrazolinones. In general, 1-substituted-5(4H)-tetrazolinones can be synthesized according to the known processes represented by the following reaction equations: The above-mentioned processes have been found to be not useful as industrially utilizable processes due to the following points: 1) the reaction is of non-aqueous nature with the reaction procedures and reaction conditions being difficult to select, 2) isocyanates, particularly methylisocyanate and heterocyclic series isocyanates, the starting compounds, are difficult to handle and manufacture, 3) in case of a reaction using aluminum chloride, only 1 mol of sodium azide reacts per 1 mol of isocyanate with the remaining two mols of unreacted sodium azide being decomposed and thrown away, in spite of sodium azide being an expensive material, 4) aluminum chloride to be used as catalyst in the reaction is difficult to be disposed by drainage, and 5) azidotrimethylsilane is more expensive than sodium azide, while the yield of product is sometimes poor even under a prolonged reaction time. Further, Journal of Organic Chemistry, 33 (I), 262-265 (1968) discloses the following reaction with a yield of 45%: It has been found that 1-substituted-5(4H)-tetrazolinones of the general formula (I) wherein R 1 represents C 1-12 alkyl, C 1-6 haloalkyl, C 2-8 alkoxyalkyl, C 2-8 -alkylthioalkyl, C 3-8 cycloalkyl, C 3-8 alkenyl, C 3-8 haloalkenyl, C 3-8 alkynyl, or a group represented by the general formula wherein Ar represents unsubstituted phenyl, or a phenyl group having a substituent or substituents optionally selected from the group consisting of halogen, C 1-4 alkyl, C 1-4 haloalkyl, C 1-4 alkoxy, C 1-4 haloalkoxy, C 1-4 alkylthio, C 1-4 haloalkylthio, -NR 4 R 5 , C 1-4 -alkoxy-carbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocyclyl-oxy, methylene dioxy, halomethylene dioxy, ethylene dioxy, haloethylene dioxy, cyano and nitro; or Ar represents unsubstituted naphthyl, or a substituted naphthyl group having a substituent or substituents optionally selected from the group consisting of halogen, C 1-4 alkyl, C 1-4 haloalkyl, C 1-4 alkoxy, C 1-4 haloalkoxy, C 1-4 alkylthio, C 1-4 haloalkylthio, -NR 4 R 5 , C 1-4 alkoxy-carbonyl, carboxyl, optionally substituted phenoxy, optionally substituted heterocyclyl oxy, methylene dioxy, halomethylene dioxy, ethylene dioxy, haloethylene dioxy, cyano and nitro, or Ar represents a five- to seven-membered heterocyclic ring or their benzologues or their substituted derivatives having a substituent or substituents optionally selected from the group consisting of halogen, C 1-4 alkyl, C 1-4 haloalkyl, C 1-4 alkoxy, C 1-4 haloalkoxy, C 1-4 alkylthio, C 1-4 haloalkylthio, -NR 4 R 5 , C 1-4 alkoxy-carbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocyclyl-oxy, methylene dioxy, halomethylene dioxy, ethylene dioxy, haloethylene dioxy, cyano and nitro, R 3 represents hydrogen or C 1-4 alkyl, R 4 and R 5 may be the same or different and represent hydrogen or C 1-4 alkyl, and n represents 0, 1, 2 or 3, are obtained when 1-substituted-5(4H)-tetrazolinethiones of the general formula (II) wherein R 1 has the same meaning as mentioned above, are reacted with ethylene oxides of the general formula (III) wherein R 2 represents hydrogen, methyl or ethyl, in the presence of a base and in the presence of water or an alcohol or a solvent mixture thereof. Surprisingly, it has been found that the process according to the present invention has the following advantages as compared with the above-mentioned prior art processes wherein isocyanates are reacted with sodium azide: 1) an excellent yield is obtained, 2) 1-substituted-5(4H)-tetrazolinethiones represented by the general formula (II) and employed as starting materials according to the present invention are less expensive than the starting materials previously used for the production of 1-substituted-5(4H)-tetrazolinones, yet capable of producing a variety of compounds, 3) the reaction solvents employed are not expensive, and 4) the reaction can be advantageously applied to an industrial scale operation. In the production process according to the present invention, if use is made, as starting materials, of 1-phenyl-5(4H)-tetrazolinethione and propylene oxide, for example, the reaction can be expressed as follows: In the general formula (II) representing 1-substituted-5(4H)-tetrazolinethiones, preferably R 1 represents methyl, ethyl, n-propyl, isopropyl, n-(sec-, iso-, or tert-)butyl, n-hexyl, trifluoromethyl, difluoromethyl, chlorodifluoromethyl, 2,2,2-trifluoroethyl, perfluoropropyl, perfluorohexyl, methoxyethyl, ethoxymethyl, ethoxyethyl, propoxyethyl, butoxyethyl, methylthioethyl, methylthiomethyl, methylthiopropyl, ethylthiomethyl, ethylthioethyl, propylthioethyl, butylthioethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, allyl, chloroallyl, butenyl, hexenyl, propargyl, or a group represented by the general formula wherein Ar represents unsubstituted phenyl or a phenyl group having a substituent or substituents optionally selected from the group consisting of fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, difluoromethyl, chlorodifluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, methoxy, ethoxy, propoxy, butoxy, difluoromethoxy, chlorodifluoromethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, propylthio, difluoromethylthio, trifluoromethylthio, 2,2,2-trifluoroethylthio, dimethylamino, diethylamino, methoxycarbonyl, ethoxycarbonyl, butoxycarbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocyclyl oxy, (wherein the hetero ring of said heterocyclyl-oxy is selected from the group consisting of imidazole, pyrazole, triazole, oxazole, isoxazole, benzoxazole, thiazole, isothiazole, benzothiazole, oxadiazole, thiadiazole, tetrazole, pyridine, quinoline, isoquinoline, pyrimidine, pyridazine, pyrazine, quinazoline, quinoxaline, triazine, thiophene, benzothiophene, furan and benzofuran), methylenedioxy, difluoromethylenedioxy, ethylenedioxy, chlorodifluoroethylenedioxy, difluoroethylenedioxy, trifluoroethylenedioxy, tetrafluoroethylenedioxy, cyano and nitro; or Ar represents unsubstituted naphthyl or a substituted naphthyl group having a substituent or substituents optionally selected from the group consisting of fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, difluoromethyl, chlorodifluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, methoxy, ethoxy, propoxy, butoxy, difluoromethoxy, chlorodifluoromethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, propylthio, difluoromethylthio, trifluoromethylthio, 2,2,2-trifluoroethylthio, dimethylamino, diethylamino, methoxycarbonyl, ethoxycarbonyl, butoxycarbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocycyl-oxy, (wherein the hetero ring of said heterocyclyl-oxy is selected from the group consisting of imidazole, pyrazole, triazole, oxazole, isoxazole, benzoxazole, thiazole, isothiazole, benzothiazole, oxadiazole, thiadiazole, tetrazole, pyridine, quinoline, isoquinoline, pyrimidine, pyridazine, pyrazine, quinazoline, quinoxaline, triazine, thiophene, benzothiophene, furan and benzofuran), methylenedioxy, difluoromethylenedioxy, ethylenedioxy, chlorodifluoroethylenedioxy, difluoroethylenedioxy, trifluoroethylenedioxy, tetrafluoroethylenedioxy, cyano and nitro; or Ar represents an unsubstituted five- to six-membered heterocyclic ring and their benzologues, (wherein said hetero ring is selected from the group consisting of imidazole, pyrazole, triazole, oxazole, isoxazole, benzoxazole, thiazole, isothiazole, benzothiazole, oxadiazole, thiadiazole, tetrazole, pyridine, quinoline, isoquinoline, pyrimidine, pyridazine, pyrazine, quinazoline, quinoxaline, triazine, thiophene, and furan), a five- or six-membered heterocyclic ring or their benzologues (wherein said heterocyclic ring is selected from the group consisting of imidazole, pyrazole, triazole, oxazole, isoxazole, benzoxazole, thiazole, isothiazole, benzthiazole, oxadiazole, thiazole, tetrazole, pyridine, quinoline, isoquinoline, pyrimidine, pyridazine, pyrazine, quinazoline, quinoxaline, triazine, thiophene and furan), having a substituent or substituents optionally selected from the group consisting of fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, difluoromethyl, chlorodifluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, methoxy, ethoxy, propoxy, butoxy, difluoromethoxy, chlorodifluoromethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, propylthio, difluoromethylthio, trifluoromethylthio, 2,2,2-trifluoroethylthio, dimethylamino, diethylamino, methoxycarbonyl, ethoxycarbonyl, butoxycarbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocyclyl-oxy, (wherein the hetero ring of said heterocyclyl-oxy is selected from the group consisting of imidazole, pyrazole, triazole, oxazole, isoxazole, benzoxazole, thiazole, isothiazole, benzothiazole, oxadiazole, thiadiazole, tetrazole, pyridine, quinoline, isoquinoline, pyrimidine, pyridazine, pyrazine, quinazoline, quinoxaline, triazine, thiophene, benzothiophene, furan and benzofuran), methylene dioxy, difluoromethylene dioxy, ethylene dioxy, chlorodifluoroethylene dioxy, difluoroethylene dioxy, trifluoroethylene dioxy, tetrafluoroethylene dioxy, cyano and nitro, R 3 represents hydrogen or methyl and n is an integer of 0, 1 or 2. The 1-substituted-5(4H)-tetrazolinethiones of the formula (II) can be synthesized, for example, by reacting a compound represented by the general formula (IV) wherein R 1 has the same meaning as mentioned before, with one equivalent of sodium azide in water. This reaction is disclosed in U.S. Patent No. 2,386,869 and Japanese Laid-open No. Sho 53-50, 169. The compounds of formula (IV), used as starting materials in this reaction, are well known in the field of organic chemistry. For an alternative route to 1-aryl-5(4H)-tetrazolinethiones of the formula (II), namely by reacting 4-aryl-thiosemicarbazides with nitrous acid (HNO 2 ), see "Berichte", Vol. 28, pp. 74-76 (1895). The ethylene oxides represented by the general formula (III) are also well known in organic chemical field. As ethylene oxides represented by the general formula (III) there may be exemplified ethylene oxide, propylene oxide, and 1,2-epoxybutane and, as most preferred examples, may be mentioned ethylene oxide and propylene oxide. In carrying out the process according to the present invention use is made of suitable diluents. As examples of such diluents there may be mentioned water and alcohols such as, for example, methanol, ethanol, isopropanol, butanol and solvent mixtures thereof. The process of the present invention is carried out in the presence of bases which include hydroxides, carbonates and bicarbonates of alkali metals or alkaline earth metals such as, for example, sodium bicarbonate, potassium bicarbonate, sodium carbonate, potassium carbonate, lithium hydroxide, sodium hydroxide, potassium hydroxide and calcium hydroxide. The process according to the present invention can be conducted at temperatures in a substantially wide range. In general, the reaction is carried out at temperatures in the range of from -30°C to +50°C, preferably about 0°C to about +30°C. The reaction is preferably carried out at normal pressure but it may be carried out at elevated or reduced pressure as well. The reaction time may range from one hour to twelve hours, preferably from one hour to six hours. In carrying out the present process, from 1.0 mol to 1.3 mol of ethylene oxides represented by the general formula (III) are reacted with 1 mol of 1-substituted-5(4H)-tetrazolinethiones represented by the general formula (II) in the presence of a diluent such as, for example, a solvent mixture consisting of water and ethanol and from 1 mol to 1.2 mol of a base, so as to obtain the aimed compounds. 1-Substituted-5(4H)-tetrazolinones are useful as starting materials for the production of herbicidal compounds as disclosed by U.S. Patents Nos. 4 956 469, 5 003 075 and 5 019 152; EP-A-146 279 and EP-A-202 929. The process according to the present invention will be further explained by way of the following examples. EXAMPLES: Synthesis Example 1 Sodium hydroxide (0.84 g) was dissolved in water (1 ml), followed by addition of 1-phenyl-5(4H)-tetrazolinethione (3.56 g) thereto so as to form a uniform solution. The thus obtained solution was diluted with ethanol (25 ml) and then cooled to 0°C, followed by dropwise addition of propylene oxide (1.51 g) thereto with the temperature being kept as it had been. After a 30 minute-stirring at 0°C, the reaction was continued for five hours at room temperature. The solvent was then removed from the reaction product by a reduced pressure distillation, followed by addition of water (30 ml) to the residue from which unsoluble oil content was washed away with ethyl acetate. The resulting aqueous layer was taken and acidified with diluted hydrochloric acid, followed by filtration of the separated crystals. After washing of the thus obtained crystals with cold water and then drying, there was obtained 1-phenyl-5(4H)-tetrazolinone (2.33 g) having a melting point (m.p.) in the range of from 191 to 192°C. Synthesis Example 2 Sodium hydroxide (0.52 g) was dissolved in water (1 ml), followed by addition of 1-(2-chlorophenyl)-5(4H)-tetrazolinethione (2.13 g) thereto so as to form a uniform solution. The thus obtained solution was diluted with ethanol (25 ml) and then cooled to 0°C, followed by dropwise addition of propylene oxide (0.76 g) thereto with the temperature being kept as it had been. After a 30 minute-stirring at 0°C, the reaction was continued for five hours at room temperature. The solvent was then removed from the reaction product by a reduced pressure distillation, followed by addition of water (30 ml) to the residue from which unsoluble oil content was washed away with ethyl acetate. The resulting aqueous layer was taken and acidified with hydrochloric acid, followed by extraction of the separated crystals with ethyl acetate and drying of that solution over anhydrous magnesium sulfate. Upon removal of the solvent by a reduced pressure distillation there was obtained 1-(2-chlorophenyl)-5(4H)-tetrazolinone (1.92 g) having a m.p. in the range of from 124 to 126°C. Synthesis Example 3 Use was made of 1-methyl-5(4H)-tetrazolinethione (5.81 g), sodium hydroxide (2.60 g) and propylene oxide (3.78 g), which were reacted in a similar manner as that employed in Synthesis Examples 1 and 2. The resulting aqueous layer was acidified and then evaporated to dryness at a reduced pressure followed by the resulting residue being extracted in ethyl acetate and filtration. Upon removal of the solvent by a reduced pressure distillation there was obtained 1-methyl-5(4H)-tetrazolinone (3.66 g) having a m.p. in the range of from 114 to 116.5°C. Comparative Synthesis Example According to a description given in "Journal of Organic Chemistry", 33 (1), 262-265 (1968), use was made, for a reaction, of 1-phenyl-5(4H)-tetrazolinethione (7.1 g), sodium hydroxide (1.7 g) and cyclohexene oxide (4.1 g) to obtain 1-phenyl-5(4H)-tetrazolinone (3.1 g, in a yield of 48%). The present reaction produced, at the working-up, matter insoluble in alkali, thus bringing about difficulty in the purification of the aimed product. In the following Table 1 there are shown further compounds of the above formula (I) that were synthesized in a manner analogous to that described in each of the foregoing Synthesis Examples 1-3, together with the three compounds obtained according to said foregoing Examples. Ex. No. R 1 R 2 Base Solvent Yield (%) Physical constant of product (I) 1 Phenyl Methyl Sodium-hydroxide Ethanol 72 m.p. 191-192°C 1a Phenyl Methyl Potassium-hydroxide Ethanol 82 m.p. 191-192°C 1b Phenyl Methyl Sodium-hydroxide Water 88 m.p. 191-192°C 1c Phenyl Ethyl Sodium-hydroxide Ethanol 85 m.p. 191-192°C 2 2-chlorophenyl Methyl Sodium-hydroxide Ethanol 97 m.p. 124-126°C 2a 2-chlorophenyl Hydrogen Sodium-hydroxide Ethanol 80 m.p. 124-126°C 3 Methyl Methyl Sodium-hydroxide Ethanol 73 m.p. 114-116.5°C 4 2-chloro-3-methylphenyl Methyl Sodium-hydroxide Ethanol 81 m.p. 121-123.5°C 5 3,5-dichlorophenyl Methyl Sodium-hydroxide Ethanol 91 m.p. 188-189.5°C 6 2-chloro-4-trifluoromethylphenyl Methyl Sodium-hydroxide Ethanol 87 m.p. 155.5-157°C 7 Benzyl Methyl Sodium-hydroxide Ethanol 84 m.p. 145.5-147°C 8 3,4-tetrafluoroethylenedioxyphenyl Methyl Sodium-hydroxide Ethanol 86 m.p. 123-123.5°C 9 2-chloro -5-pyridyl-methyl Methyl Sodium-hydroxide Ethanol 82 m.p. 141-142.5°C In addition to the above-mentioned concrete examples, the following compounds can also be obtained in high yields according to the reaction conditions mentioned above employed in the present invention. 1-(ethyl)-5(4H)-tetrazolinone, 1-(n-propyl)-5(4H)-tetrazolinone, 1-(isopropyl)-5(4H)-tetrazolinone, 1-(tert-butyl)-5(4H)tetrazolinone, 1-(cyclopropyl)-5(4H)-tetrazolinone, 1-(cyclopentyl)-5(4H)-tetrazolinone, 1-(cyclohexyl)-5(4H)-tetrazolinone, 1-(2,2,2-trifluoroethyl)-5(4H)-tetrazolinone, 1-(methoxyethyl)-5(4H)-tetrazolinone, 1-(ethylthioethyl)-5(4H)-tetrazolinone, 1-(methylthioethyl)-5(4H)-tetrazolinone, 1-(allyl)-5(4H)-tetrazolinone, 1-(3-chloroallyl)-5(4H)-tetrazolinone, 1-(propargyl)-5(4H)-tetrazolinone, 1-(2-fluorophenyl)-5(4H)-tetrazolinone, 1-(3-chlorophenyl)-5(4H)-tetrazolinone, 1-(3-trifluoromethylphenyl)-5(4H)-tetrazolinone, 1-(4-trifluoromethylphenyl)-5(4H)-tetrazolinone, 1-(4-chlorophenyl)-5(4H)-tetrazolinone, 1-(2-methylphenyl)-5(4H)-tetrazolinone, 1-(3-methylphenyl)-5(4H)-tetrazolinone, 1-(4-methylphenyl)-5(4H)-tetrazolinone, 1-(2-methoxyphenyl)-5(4H)-tetrazolinone, 1-(4-methoxyphenyl)-5(4H)-tetrazolinone, 1-(4-trifluoromethoxyphenyl)-5(4H)-tetrazolinone, 1-(4-trifluoromethylphenyl)-5(4H)-tetrazolinone, 1-(3-propylphenyl)-5(4H)-tetrazolinone, 1-(4-tert-butylphenyl)-5(4H)-tetrazolinone, 1-(2,4-dichlorophenyl)-5(4H)-tetrazolinone, 1-(2,6-dichlorophenyl)-5(4H)-tetrazolinone, 1-(2-chloro-6-methylphenyl)-5(4H)-tetrazolinone, 1-(3-chloro-4-trifluoromethylphenyl)-5(4H)-tetrazolinone, 1-[4-(2,4-dichlorophenoxy)phenyl]-5(4H)-tetrazolinone, 1-[4-(2-chloro-4-trifluoromethylphenoxy)phenyl]-5(4H)-tetrazolinone, 1-[4-(2,6-dichloro-4-trifluoromethylphenoxy)phenyl]-5(4H)-tetrazolinone, 1-(3-phenoxyphenyl)-5(4H)-tetrazolinone, 1-(3,4-difluoromethylenedioxyphenyl)-5(4H)-tetrazolinone, 1-[4-(3,5-dichloropyridinyloxy)-phenyl]-5(4H)-tetrazolinone, 1-[3,5-bis(trifluoromethyl)-phenyl]-5(4H)-tetrazolinone, 1-(2-cyanophenyl)-5(4H)-tetrazolinone, 1-(4-chloro-2-fluoro-5-isopropoxyphenyl)-5(4H)-tetrazolinone, 1-[4-chloro-2-fluoro-5-(methoxycarbonyl)methoxyphenyl]-5(4H)-tetrazolinone, 1-[4-chloro-2-fluoro-5-(n-pentyloxycarbonyl)methoxyphenyl]-5-(4H)-tetrazolinone, 1-[7-fluoro-4-ethoxy-2H-1,4-benzoxazine-3(4H)-one-6-yl]-5(4H)-tetrazolinone, 1-[7-fluoro-4-propargyl-2H-1,4-benzoxazine-3(4H)-one-6-yl]-5(4H)-tetrazolinone, 1-(6-fluoro-4-propargyl-2H-1,3-benzoxazole-2-one-5-yl)-5(4H)-tetrazolinone, 1-(6-fluoro-4-propargyl-2H-1,3-benzothiazole-2-one-5-yl)-5(4H)-tetrazolinone, 1-[4-chloro-2-fluoro-5-(methanesulphonylamino)-phenyl]-5(4H)-tetrazolinone, 1-(3-tert-butylisoxazole-5-yl)-5(4H)-tetrazolinone, 1-(5-tert-butylisoxazole-5-yl)-5(4H)-tetrazolinone, 1-(5-tert-butyl-1,3,4-thiadiazol-2-yl)-5(4H)-tetrazolinone, 1-(5-trifluoromethylpyridine-2-yl)-5(4H)-tetrazolinone, and 1-(3-chloro-5-trifluoromethyl-pyridine-2-yl)-5(4H)-tetrazolinone.

Claims: Process for the preparation of 1-substituted-5(4H)-tetrazolinones of the general formula (I) wherein R 1 represents C 1-12 alkyl, C 1-6 haloalkyl, C 2-8 alkoxyalkyl, C 2-8 -alkylthioalkyl, C 3-8 cycloalkyl, C 3-8 alkenyl, C 3-8 haloalkenyl, C 3-8 alkynyl, or a group represented by the general formula wherein Ar represents unsubstituted phenyl, or a phenyl group having a substituent or substituents optionally selected from the group consisting of halogen, C 1-4 alkyl, C 1-4 haloalkyl, C 1-4 alkoxy, C 1-4 haloalkoxy, C 1-4 alkylthio, C 1-4 haloalkylthio, -NR 4 R 5 , C 1-4 -alkoxy-carbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocyclyl-oxy, methylene dioxy, halomethylene dioxy, ethylene dioxy, haloethylene dioxy, cyano and nitro; or Ar represents unsubstituted naphthyl, or a substituted naphthyl group having a substituent or substituents optionally selected from the group consisting of halogen, C 1-4 alkyl, C 1-4 haloalkyl, C 1-4 alkoxy, C 1-4 haloalkoxy, C 1-4 alkylthio, C 1-4 haloalkylthio, -NR 4 R 5 , C 1-4 alkoxy-carbonyl, carboxyl, optionally substituted phenoxy, optionally substituted heterocyclyl oxy, methylene dioxy, halomethylene dioxy, ethylene dioxy, haloethylene dioxy, cyano and nitro, or Ar represents a five- to seven-membered heterocyclic ring or their benzologues or their substituted derivatives having a substituent or substituents optionally selected from the group consisting of halogen, C 1-4 alkyl, C 1-4 haloalkyl, C 1-4 alkoxy, C 1-4 haloalkoxy, C 1-4 alkylthio, C 1-4 haloalkylthio, -NR 4 R 5 , C 1-4 alkoxy-carbonyl, carboxy, optionally substituted phenoxy, optionally substituted heterocyclyl-oxy, methylene dioxy, halomethylene dioxy, ethylene dioxy, haloethylene dioxy, cyano and nitro, R 3 represents hydrogen or C 1-4 alkyl, R 4 and R 5 may be the same or different and represent hydrogen or C 1-4 alkyl, and n represents 0, 1, 2 or 3, characterised in that 1-substituted-5(4H)-tetrazolinethiones of the general formula (II) wherein R 1 has the same meaning as mentioned above, are reacted with ethylene oxides of the general formula (III) wherein R 2 represents hydrogen, methyl or ethyl, in the presence of a base and in the presence of water or an alcohol or a solvent mixture thereof. The process according to claim 1, wherein the reaction is carried out at temperatures in the range from -30°C to +50°C. The process according to claim 1, wherein said solvent is selected from the group consisting of water, methanol, ethanol and a mixture thereof. The process according to claim 1, wherein said ethylene oxide is selected from the group consisting of ethylene oxide, propylene oxide, and 1,2-epoxybutane. The process according to claim 1, wherein said base is selected from the group consisting of sodium hydroxide and potassium hydroxide.

Inventors: NARABU SHIN-ICHI, WATANABE YUKIYOSHI, YANAGI AKIHIKO, NARABU, SHIN-ICHI, WATANABE, YUKIYOSHI, YANAGI, AKIHIKO
Applicants: BAYER AGROCHEM KK, NIHON BAYER AGROCHEM K.K.
Application year: 1994
Main classification: C07D257
IPC codes: C07D257, C07D405, C07D401